From owner-freebsd-hackers Wed May 24 11:20:55 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from nadia.s.bawue.de (nadia.s.bawue.de [193.197.11.52]) by hub.freebsd.org (Postfix) with ESMTP id 88B7537B87F for ; Wed, 24 May 2000 11:20:50 -0700 (PDT) (envelope-from tf@wurbl.wn.bawue.de) Received: from wurbl.wn.bawue.de (uucp@localhost) by nadia.s.bawue.de (8.9.3/8.9.3) with UUCP id UAA14273 for freebsd.org!freebsd-hackers; Wed, 24 May 2000 20:20:48 +0200 (CEST) Posted-Date: Wed, 24 May 2000 20:20:48 +0200 (CEST) Received: from uucp (helo=prian.bk.int) by wurbl.bk.int with local-esmtp (Exim 3.03 #1) id 12ufif-00035U-00 for freebsd-hackers@freebsd.org; Wed, 24 May 2000 20:17:26 +0200 Date: Wed, 24 May 2000 20:11:31 +0200 (CEST) From: Thomas Faehnle Subject: Need help debugging a crash (PR kern/18685) To: freebsd-hackers@freebsd.org MIME-Version: 1.0 Content-Type: TEXT/plain; CHARSET=US-ASCII Message-Id: Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Hi, I'm trying to assist in debugging the crash reported as kern/18685-- apparently Greg is unable to reproduce the problem on his machine. The error | Fatal trap 12: page fault while in kernel mode | fault virtual address = 0x69666f27 | fault code = supervisor read, page not present | instruction pointer = 0x8:0xc0158c14 | stack pointer = 0x10:0xc3dd7bf8 | frame pointer = 0x10:0xc3dd7c0c | code segment = base 0x0, limit 0xfffff, type 0x1b | = DPL 0, pres 1, def32 1, gran 1 | processor eflags = interrupt enabled, resume, IOPL = 0 | current process = 974 (make) | interrupt mask = none | kernel: type 12 trap, code=0 | Stopped at dscheck+0x104: movl 0xb8(%esi),%edx | | db> trace | dscheck(c1413728,c08c6900) at dscheck+0x104 | diskstrategy(c1413728,c0845e80,c1413728,0,c3dd7c4c) at diskstrategy+0xad | spec_strategy(c3dd7c70,c3dd7c58,c0208f7d,c3dd7c70,c3dd7c8c) at spec_strategy+0x8c | spec_vnoperate(c3dd7c70,c3dd7c8c,c02089e5,c3dd7c70,c3dd7ce4) at spec_vnoperate+0x15 | ufs_vnoperatespec(c3dd7c70,c3dd7ce4,c1413728,0,c028ae80) at ufs_vnoperatespec+0x15 | ... occurs at line 198 ("labelsect = lp->d_partitions[LABEL_PART].p_offset;") of /sys/kern/subr_diskslice.c due to a bogus "struct diskslices" pointer (the second argument of dscheck(), "ssp"). I can't do a crash dump, since ddb refuses to step past the instruction that triggered the trap (saying "panic" just repeats the above message). I can't catch the "ssp" pointer when it gets corrupted either, since watchpoints don't seem to work in ddb (at least not on kernel memory). What can I do to help getting this fixed? Suggestions? Thomas -- Thomas Faehnle, Am Sommerrain 12, D-71522 Backnang | MIME mail welcome mail: tf@wurbl.wn.bawue.de * phone: +49 7191 954671 | PGP key available To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message